I thought the same thing when I started, took a few days to get to the negative numbers, then kind of accepted some people are just really good. After I shot aa -5 on 9 holes and missing 3 makeable putts I realized its entirely possible to go low, the solution.......practice, practice, practice.
The LPGA is an unlimited qualifier, people will bow out after going -2 through 3 holes since the first 3 holes are all birdie holes. Also play with better players, their tips are valuable.